Re: <none>

Singular Shell ( taoj@ucs.orst.edu )
Mon, 14 Jul 1997 17:56:55 -0700 (PDT)

What about doing Rieveld refinement, then using Utax program to do valence
calculation with the refined crystal structure parameters? The
calculation is based on the correlation between valency and bond lengths.
But if in LI0.3Mn2O4 we have two atoms disordered in one site, I am not
sure how reliable the calculation will be.

The question leads to something I have been wondering for a while. In
rieveld refinement when should we use M^n+ (ions) instead of M (atoms)?
Or the difference in scattering factors is just too small to matter?

Tao
7/14/97

On Mon, 14 Jul 1997, Ulrich Koops wrote:

> Hello
>
> Is it possible to distinguish the valence state of an ion, say manganese,
> in different compounds of the same structure (say LiMn2O4 from
> Li0.3Mn2O4, both Fd3m) using x-ray powderdiffractometry? Can it be done
> or is it not possible to measure this difference?
>
> Thanks for all comments...
>
> Ulrich Koops
>
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